What is the differances between the 42RE transmission, 46RE transmission, 545RFE transmission and is the 545RFE transmission the HD in compairison to the other two?......from what I read the 545RFE transmission is concidered a high performance 5 speed auto......thx for the feedback.

 

did a google search and found that it supports a higher towing capacity, smoother shifts and better fuel economy. i think the most important feature though is the Electronically Modulated Converter Clutch (EMCC). it electronicly modulates the torque converter for partial engagement, providing more power in high demand scenarios. this is just stuff i found online, im no expert on automatic transmissions (but i have changed several). in fact if i wanted a perfomance transmission i would put a stick shift in there.

 

Its pretty much like anyone would suspect, larger clutches, better torque converters. Overall better performance due to larger/stronger parts.

Check this website

http://www.transmissioncenter.net/dodge.htm

 

The 45RFE and 545RFE offer a "second" 2nd gear (called, 2 Prime). When you go to pass someone in a typical transmission, it will kick down into 2nd gear. In this one, it kicks down into 2nd Prime.

(5)45RFE
1 3.0:1
2 1.67:1
2P 1.5:1
3 1.0:1
4 0.75:1
5 0.67:1 (545RFE only)
R 3.0:1

46RE
1 2.45:1
2 1.45:1
3 1.0:1
4 0.69:1
R 2.21:1

42RE
1 2.74:1
2 1.54:1
3 1.0:1
4 0.69:1
R 2.21:1